addon or hack?

Seeing quite a few people in bg's whose health appears to me to be low but isn't. A few others have mentioned it too. They'll appear to have for instance 2k/30k health but kill shot, hammer, etc... isn't up. Clearly they're at full health they just have something that is affecting my unit frames. Anyone know what it might be?

yea, because its clearly other people's fault that you are altering your ui and what not. if there are "quite a few" of these cases, then id suggest that you revert the changed nameplates or whatever you have done. :)